1. Field
One embodiment of the invention relates to an image processing apparatus configured to convert the frame rate of moving image data and an image processing method applied to the image processing apparatus.
2. Description of the Related Art
A frame interpolation technique which inserts a new frame between frames in moving image data is a technique to display the moving image data smoothly. In the frame interpolation process, for example, the motion vectors between successive frames in a time series are calculated. Then, an interpolation frame to be inserted between the frames is generated by motion compensation using the calculated motion vectors.
Jpn. Pat. Appln. KOKAI Publication No. 2003-69961 discloses an image processing apparatus which converts moving image data of a first frame rate into moving image data of a second frame rate by generating interpolation frames by motion compensation using motion vectors. The image processing apparatus determines that no interpolation frame by motion compensation needs to be generated and then outputs the original image frame as an interpolation frame, if a scene change is detected between frames of a moving image or the frames are determined to be stationary since no motion is found between the frames.
Moving image data may include redundant frames. A redundant frame is generated by, for example, copying the preceding frame. Redundant frames are inserted into the moving image data by, for example, a user's editing or a conversion of the frame rate at a website that provides moving image data.
When a frame interpolation process is executed on moving image data including redundant frames, interpolation frames based on the redundant frames are generated, thus degrading the quality of the moving image. For example, the same image is further generated for an interpolation frame from the preceding frame (copy source frame) and a redundant frame (copy destination frame) which is a copy of the preceding frame. If such a moving image is reproduced, the moving image may not be smoothly displayed, for example, an object moving in the original moving image may appear stationary.